ISO 17541:2014 pdf free

ISO 17541:2014 pdf free.Plastics – Quantitative evaluation of scratch-induced damage and scratch visibility
This test method provides a quantitative evaluation of scratch damage and visibility on polymer and coated surfaces. Scratching is generated by a scratch tip capable of area-contact or line-contact on the material surface and can be induced under a constant normal load or a linearly increasing load.
The scratch damage index (SDI), the severity of surface damage caused by scratching under a constant normal load condition, is determined by comparing the Euclidean distance or percent difference in the luminance between colour coordinates of the scratched surface and the ones of the unscratched surface.SDI is defined as a set of the degree of scratch damage (or percent difference in luminance) and scratch strength (or scratch resistance) values, as a quantitative determination.
The scratch visibility index (SVI), the onset point of scratch visibility where the surface damage can be perceived by the naked eye, is determined under a linearly increasing load condition and defined as a set of intensity, saturation, which are two of three coordinates in HSI colour model, and scratch resistance value.
The instrumented scratch machine consists of a load device, position sensor, specimen stage, clamping devices, and scratch tip with a preferred geometry. An environmental chamber can also be added for testing at non-ambient condition. For evaluation after scratching, tools such as optical microscopes,flatbed scanners, profilometer, and colour analysis software are used.
The atmosphere used for testing shall be the same as that used for conditioning, as specified in accordance with ISO 291 or the appropriate material specification. If scratch tests are to be conducted at temperatures other than the room temperature, an environmental chamber shall be used to maintain the scratch tip and the specimen at the desired temperature. Prior to testing, the scratch tip and specimen shall be conditioned in the environmental chamber for not less than 30 min.
In order to quantitatively determine the scratch damage, it is recommended that one of the combinations of constant loads and test speeds specified in Table 1 is used over a scratch length of 100 mm. It is permissible to use scratch lengths other than 100 mm but this shall be noted in the report. However, the scratch length shall be at least 50 mm long.ISO 17541 pdf download.